/Engine/Source/Runtime/SlateCore/Public/Application/SlateWindowHelper.h
Make BringMeToFront first among its peers. i.e. make it the last window in its parent's list of child windows.
The top-most window whose children were re-arranged
static [TSharedRef](API\Runtime\Core\Templates\TSharedRef)< [SWindow](API\Runtime\SlateCore\Widgets\SWindow) > BringToFrontInParent ( const [TSharedRef](API\Runtime\Core\Templates\TSharedRef)< [SWindow](API\Runtime\SlateCore\Widgets\SWindow) > & WindowToBringToFront )